1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25 /*
26 * Copyright 2013 Nexenta Systems, Inc. All rights reserved.
27 */
28
29 #include <mdb/mdb_modapi.h>
30 #include <sys/list.h>
31
32 typedef struct list_walk_data {
33 uintptr_t lw_head; /* address of list head */
34 size_t lw_size; /* size of list element */
35 size_t lw_offset; /* list element linkage offset */
36 void *lw_obj; /* buffer of lw_size to hold list element */
37 uintptr_t lw_end; /* last node in specified range */
38 const char *lw_elem_name;
39 int (*lw_elem_check)(void *, uintptr_t, void *);
40 void *lw_elem_check_arg;
41 } list_walk_data_t;
42
43 /*
44 * Initialize a forward walk through a list.
45 *
46 * begin and end optionally specify objects other than the first and last
47 * objects in the list; either or both may be NULL (defaulting to first and
48 * last).
49 *
50 * list_name and element_name specify command-specific labels other than
51 * "list_t" and "list element" for use in error messages.
52 *
53 * element_check() returns -1, 1, or 0: abort the walk with an error, stop
54 * without an error, or allow the normal callback; arg is an optional user
55 * argument to element_check().
56 */
57 int
list_walk_init_range(mdb_walk_state_t * wsp,uintptr_t begin,uintptr_t end,const char * list_name,const char * element_name,int (* element_check)(void *,uintptr_t,void *),void * arg)58 list_walk_init_range(mdb_walk_state_t *wsp, uintptr_t begin, uintptr_t end,
59 const char *list_name, const char *element_name,
60 int (*element_check)(void *, uintptr_t, void *), void *arg)
61 {
62 list_walk_data_t *lwd;
63 list_t list;
64
65 if (list_name == NULL)
66 list_name = "list_t";
67 if (element_name == NULL)
68 element_name = "list element";
69
70 if (mdb_vread(&list, sizeof (list_t), wsp->walk_addr) == -1) {
71 mdb_warn("failed to read %s at %#lx", list_name,
72 wsp->walk_addr);
73 return (WALK_ERR);
74 }
75
76 if (list.list_size < list.list_offset + sizeof (list_node_t)) {
77 mdb_warn("invalid or uninitialized %s at %#lx\n", list_name,
78 wsp->walk_addr);
79 return (WALK_ERR);
80 }
81
82 lwd = mdb_alloc(sizeof (list_walk_data_t), UM_SLEEP);
83
84 lwd->lw_size = list.list_size;
85 lwd->lw_offset = list.list_offset;
86 lwd->lw_obj = mdb_alloc(list.list_size, UM_SLEEP);
87 lwd->lw_head = (uintptr_t)&((list_t *)wsp->walk_addr)->list_head;
88 lwd->lw_end = (end == 0 ? 0 : end + lwd->lw_offset);
89 lwd->lw_elem_name = element_name;
90 lwd->lw_elem_check = element_check;
91 lwd->lw_elem_check_arg = arg;
92
93 wsp->walk_addr = (begin == 0
94 ? (uintptr_t)list.list_head.list_next
95 : begin + lwd->lw_offset);
96 wsp->walk_data = lwd;
97
98 return (WALK_NEXT);
99 }
100
101 int
list_walk_init(mdb_walk_state_t * wsp)102 list_walk_init(mdb_walk_state_t *wsp)
103 {
104 return (list_walk_init_range(wsp, 0, 0, NULL, NULL, NULL, NULL));
105 }
106
107 int
list_walk_init_named(mdb_walk_state_t * wsp,const char * list_name,const char * element_name)108 list_walk_init_named(mdb_walk_state_t *wsp,
109 const char *list_name, const char *element_name)
110 {
111 return (list_walk_init_range(wsp, 0, 0, list_name, element_name,
112 NULL, NULL));
113 }
114
115 int
list_walk_init_checked(mdb_walk_state_t * wsp,const char * list_name,const char * element_name,int (* element_check)(void *,uintptr_t,void *),void * arg)116 list_walk_init_checked(mdb_walk_state_t *wsp,
117 const char *list_name, const char *element_name,
118 int (*element_check)(void *, uintptr_t, void *), void *arg)
119 {
120 return (list_walk_init_range(wsp, 0, 0, list_name, element_name,
121 element_check, arg));
122 }
123
124 int
list_walk_step(mdb_walk_state_t * wsp)125 list_walk_step(mdb_walk_state_t *wsp)
126 {
127 list_walk_data_t *lwd = wsp->walk_data;
128 uintptr_t addr = wsp->walk_addr - lwd->lw_offset;
129 list_node_t *node;
130 int status;
131
132 if (wsp->walk_addr == lwd->lw_head)
133 return (WALK_DONE);
134
135 if (lwd->lw_end != 0 && wsp->walk_addr == lwd->lw_end)
136 return (WALK_DONE);
137
138 if (mdb_vread(lwd->lw_obj, lwd->lw_size, addr) == -1) {
139 mdb_warn("failed to read %s at %#lx", lwd->lw_elem_name, addr);
140 return (WALK_ERR);
141 }
142
143 if (lwd->lw_elem_check != NULL) {
144 int rc = lwd->lw_elem_check(lwd->lw_obj, addr,
145 lwd->lw_elem_check_arg);
146 if (rc == -1)
147 return (WALK_ERR);
148 else if (rc == 1)
149 return (WALK_DONE);
150 }
151
152 status = wsp->walk_callback(addr, lwd->lw_obj, wsp->walk_cbdata);
153 node = (list_node_t *)((uintptr_t)lwd->lw_obj + lwd->lw_offset);
154 wsp->walk_addr = (uintptr_t)node->list_next;
155
156 return (status);
157 }
158
159 void
list_walk_fini(mdb_walk_state_t * wsp)160 list_walk_fini(mdb_walk_state_t *wsp)
161 {
162 list_walk_data_t *lwd = wsp->walk_data;
163
164 mdb_free(lwd->lw_obj, lwd->lw_size);
165 mdb_free(lwd, sizeof (list_walk_data_t));
166 }
167